Maltitol increases transepithelial diffusional transfer of calcium in rat ileum

We explored the mechanism whereby maltitol causes an increase of calcium absorption in the lower small intestine using everted ileal segments of rats. Under the calcium concentrations tested (1-20mM), which enabled us to assess the diffusional calcium transfer, maltitol in the mucosal-side medium (100mM) caused a 155% greater transepithelial calcium transfer as compared with the segments incubated without sugars. The maltitol-induced increment of calcium transfer was significantly higher than those elicited by glucose, sorbitol and maltose, and this increase was completely inhibited by W7, a calmodulin antagonist. Thus, our results suggest that maltitol might modulate the permeability of calcium through paracellular path, which possibly involves the activation of calmodulin.